The invention concerns a rivet fastener, consisting of a rivet housing as well as a rivet shaft with a bolt-shaped shank, which can be inserted in the rivet housing and a head arranged or formed on this shank, greater in diameter in relationship to the shank, onto which head is arranged or formed a drilling component, whereby a stop flange is formed onto the rivet housing.
A rivet fastener of this type is described and shown in DE-C1-4,003,373. Known rivet fasteners of this type are employed where two workpieces are to be fastened securely and immovably to each other. The rivet housing is accordingly situated in the hole passing through the two workpieces, such that these two workpieces cannot move relative to each other.
Known rivet fasteners of this type cannot be installed for the mutual fastening of workpieces, which despite the mutual fastening can, or must, move relative to each other and across the longitudinal axis of the rivet fastener. It is precisely necessary, for the mutual fastening of workpieces of different materials, that these be able to move a limited amount, across the axis of the rivet fastener, in order to create, by this means, an equilibrium, in order to compensate, for example, for heat expansion. A necessity of this type exists, for example, for roof and wall casings, whereby the casing or roof elements, consisting of the most varied materials are to be fastened to the secure, e.g. metal-based substructure.
A metal blind rivet has already become known (CH-A-671,617), with which a feasibility of this type can be achieved. In this case, holes of different diameters are drilled in the two workpieces to be fastened. The rivet housing of the rivet fastener is accordingly securely seated in one workpiece and a larger hole is provided in the other workpiece, such that these two workpieces can move relative to each other. For an embodiment of this type, measures must be taken in order to be able to drill holes of differing diameters in a single step. Radially projecting drill-bit wings are provided for, for these embodiment variants, the drilling diameter of which is greater than the drilling component on the front end of the rivet fastener. But a construction of this type cannot be employed for rivet fasteners with a relatively small diameter, whereby on the basis of the deformability alone of the materials forming the rivet shaft, no radially projecting drill-bit wings of this length can be produced.